JP2003346078A - Two-dimensional code reader, image input device, method for reading two-dimensional code, image input method, its program, and recording medium recording the program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To extract desired information from a two-dimensional code with precision and at high speed and to more accurately acquire additional handwritten information on a document printed on a sheet of paper, thereby reflecting this information on the original electronic document. <P>SOLUTION: The two-dimensional code including position information, a document ID, and an error correction code on the surface of the sheet of paper is read with a pen type coordinate input device 10. During initial reading operation, the document ID included in the two-dimensional code is retained by a microcomputer 101 and error correction is directly executed. In the case of successive reads, the document ID in the two-dimensional code is replaced by the retained document ID and error correction is executed thereafter. An information processor 21 acquires from a storage device 30 a document 31 which corresponds to the document ID inputted from the pen type coordinate input device 10, and displays it. Additional information is also displayed superimposed on the ID. <P>COPYRIGHT: (C)2004,JPO

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a two-dimensional code reader, an image input device, a two-dimensional code reading method, an image input method, a program thereof, and a recording medium on which the program is recorded.

[0002]

2. Description of the Related Art In the prior art, there are several methods for digitizing information obtained by a user on a sheet of paper as shown below.

For example, Japanese Patent Laying-Open No. 7-141104 discloses a method in which a two-dimensional matrix in which coordinates are encoded is read by an optical pen and coordinates indicated by the optical pen are obtained.

In this method, the coordinates in the horizontal direction and the coordinates in the vertical direction are converted by a black-and-white pattern, respectively, and displayed on a display medium. Further, by reading the displayed black and white pattern using the optical pen, the coordinates indicated by the optical pen are obtained. However, in this method, since the error correction code is not used when converting the coordinates into the black and white pattern, a method called mutual correction is adopted for acquiring the coordinates.

In Japanese Patent Laid-Open Publication No. 2000-293303, optically readable code symbols are arranged in a matrix on a sheet of paper, and the code symbols are read by a camera simultaneously with rewriting on the sheet of paper with a pen equipped with a small camera. Discloses a method for associating coordinate information with additional information.

In this method, information unique to a document and coordinate information are simultaneously converted into a black and white pattern and printed on paper, and information obtained by retouching a document on paper with an optical pen is read in a black and white pattern. A method of acquiring the information, further acquiring the information unique to the document and the coordinate position on the paper, and adding the additional information to the original document is adopted.

Further, in Japanese Patent Application Laid-Open No. 2000-340840, a two-dimensional code read by an optical unit is decoded, a part of the code is stored, and the stored information and the information decoded by the decoding unit are separated. A method of performing a predetermined process in response to the request is disclosed. In this method, storage means for storing the decoded information is provided, and a predetermined process is performed according to the information and the information decoded by the decoding means.

[0008]

However, according to the above-mentioned Japanese Patent Laid-Open Publication No. Hei 7-141104, mutual correction becomes impossible when the unreadable pattern is common.
In this publication, in order to cope with such a problem, the coordinates are corrected using a method called prediction correction. However, in such a configuration, when the pen moves at high speed or when the pen moves discretely, In such a case, it becomes impossible to perform prediction correction, and there is a problem that coordinates cannot be obtained.

In Japanese Patent Application Laid-Open No. 2000-293303, a two-dimensional code having an error correction function is used for a black-and-white pattern to acquire information unique to a document and coordinate information even when reading with an optical pen is unstable. Since it has such a function, it is possible to read even if reading is impossible in Japanese Patent Application Laid-Open No. 7-1411043. However, in this technique, the size of the two-dimensional code becomes large, so that a wide range of paper must be photographed with an optical pen, and the quality of the read image deteriorates due to a problem such as the depth of field. Exists. This leads to a problem that it is difficult to continuously read the two-dimensional code. In order to obtain continuous rewriting information,
Since the coordinate position must be continuously obtained by reading the two-dimensional code, such a problem causes a discontinuous point of the retouched information, and causes a problem that correct retouched information cannot be obtained.

Japanese Patent Application Laid-Open No. 2000-340840 is based on the assumption that one two-dimensional code is decoded, and does not solve the problem that occurs when different two-dimensional codes are decoded.

SUMMARY OF THE INVENTION Accordingly, the present invention has been made in view of the foregoing problems, and has been made in consideration of the above circumstances, and provides a two-dimensional code reading device, a two-dimensional code reading method, a program therefor, which can accurately and quickly extract desired information from a two-dimensional code. It is an object to provide a recording medium on which the program is recorded.

Further, the present invention provides an image input apparatus, an image input method, and a program capable of more accurately acquiring handwritten information on a document printed on paper and reflecting the information in an original electronic document. And a recording medium on which the program is recorded.

[0013]

In order to achieve the above object, the present invention provides an image input means for inputting one or more two-dimensional codes printed on a print medium as an image; A two-dimensional code reader comprising: digital information conversion means for converting a dimensional code into digital information; error correction means for performing error correction on the digital information; and decoding means for decoding the digital information on which the error correction has been performed. An apparatus, wherein the error correction means comprises:
Storage means for storing a part of the digital information as known information, and replacement means for replacing a part of the digital information converted by the digital information conversion means with the known information stored in the storage means. It is characterized by.

Thus, according to the present invention, it is possible to obtain correct retouched information with high accuracy. That is, information to be corrected can be replaced with known information.
Highly accurate coordinate input becomes possible.

Further, in the above two-dimensional code input device, when the error correction means cannot correct the digital information converted by the digital information conversion means,
It is also effective to replace a part of the digital information by the replacement means with the known information and execute error correction on the partially replaced digital information.

As a result, in the present invention, it is possible to improve the error correction rate using known correct information. That is, when error correction fails, information to be corrected can be replaced with known information and error correction can be performed, so that high-speed and high-precision coordinate input can be performed.

Further, in the above two-dimensional code input device, the replacement means may continuously input two-dimensional codes from the image input means.
When the dimensional code is input as an image, it is also effective to replace a part of the digital information converted by the digital information converting means with the known information.

As a result, according to the present invention, it is possible to correctly classify the added information for different documents. That is, the replacement means operates only when the two-dimensional code is continuously read, so that when another document is rewritten, erroneous error correction is not performed by information replacement, and Can be correctly separated.

Further, in the two-dimensional code reader, it is also effective that the known information is unique to data printed on a print medium.

Thus, according to the present invention, it is possible to correctly associate the edited document with the original electronic document. That is, by converting known information into information unique to a document,
It is possible to associate the edited print document with the original electronic document.

According to the present invention, a two-dimensional code including position information on a sheet of paper and identification information for uniquely identifying electronic data printed on the sheet of paper is printed in a predetermined arrangement on a printing medium. An image input device for inputting written contents,
It is characterized by having the two-dimensional code reader described above, and position information storage means for storing the position information acquired by the two-dimensional code reader in association with the identification information.

Thus, according to the present invention, it is possible to provide an environment in which an electronic document can be freely edited and edited by associating and managing position information as drawing contents and information unique to the document.

Further, in the above image input device, electronic data specifying means for specifying the electronic data based on the identification information obtained by the two-dimensional code reading device;
When the identification information is obtained by the two-dimensional code reader, a display unit that displays the electronic data specified by the electronic data specifying unit, and superimposed on the electronic data displayed by the display unit, It is also effective to have a writing content display means for drawing the writing content based on the position information.

Thus, according to the present invention, it is possible to check the added content on the display or the like at any time, so that it is possible to provide an environment where editing by writing can be performed accurately and accurately.

Further, in the above image input apparatus, the two-dimensional code reading device may include a writing unit for writing on the print medium, and a writing detection for detecting whether or not the writing is performed by the writing unit. Means, and when the replacement means detects that the writing by the writing means is continuously performed by the writing detection means, a part of the digital information converted by the digital information conversion means. Is also effectively replaced with the known information.

Thus, according to the present invention, since the contents of the retouching can be digitized and written directly on a print medium,
The user can check the retouched contents on the display or the printed matter, and also can edit the printed matter at the same time as the editing of the electronic data, so that the user can easily grasp the relationship between the two.

According to the present invention, there is provided an image input step of inputting one or more two-dimensional codes printed on a print medium as an image, and converting the two-dimensional code input in the image input step into digital information. A two-dimensional code reading method, comprising: a digital information converting step of performing error correction on the digital information; and a decoding step of decoding the digital information on which the error correction has been performed. The correcting step stores a part of the digital information as known information,
A part of the digital information converted in the digital information conversion step is replaced with the stored known information.

Thus, according to the present invention, it is possible to obtain correct additional information with high accuracy. That is, information to be corrected can be replaced with known information.
Highly accurate coordinate input becomes possible.

Further, in the above two-dimensional code reading method, when the error correction step cannot correct an error in the digital information converted in the digital information conversion step, a part of the digital information is replaced with the known information. It is also effective to perform the error correction on the digital information partially substituted.

Thus, in the present invention, it is possible to improve the error correction rate using known correct information. That is, when error correction fails, information to be corrected can be replaced with known information and error correction can be performed, so that high-speed and high-precision coordinate input can be performed.

Further, in the above-mentioned two-dimensional code reading method, when the two-dimensional code is continuously input as an image in the image input step, the error correction step is performed by the digital information conversion step. It is also effective to replace a part of the digital information with the known information.

Thus, according to the present invention, it is possible to correctly discriminate retouched information for different documents. That is, the replacement means operates only when the two-dimensional code is continuously read, so that when another document is rewritten, erroneous error correction is not performed by information replacement, and Can be correctly separated.

Further, in the above two-dimensional code reading method, it is also effective that the known information is unique to data printed on a print medium.

Thus, according to the present invention, it is possible to correctly associate the edited document with the original electronic document. That is, by converting known information into information unique to a document,
It is possible to associate the edited print document with the original electronic document.

According to the present invention, a two-dimensional code including position information on a sheet and identification information for uniquely identifying electronic data printed on the sheet is printed on a printing medium on which a predetermined arrangement is printed. An image input method for inputting written contents,
It is characterized by comprising a two-dimensional code reading method described above, and a position information storing step of storing position information obtained by the two-dimensional code reading method in association with the identification information.

Thus, according to the present invention, it is possible to provide an environment in which the electronic document can be freely edited and edited by associating and managing the position information as the drawing content and the information unique to the document.

Further, in the above image input method, an electronic data specifying step for specifying the electronic data based on the identification information obtained by the two-dimensional code reading method, and the electronic data specifying step specified in the electronic data specifying step. A display step of displaying electronic data, and a writing content drawing step of drawing writing content based on the position information superimposed on the electronic data displayed in the display step,
It is also effective to have

Thus, according to the present invention, it is possible to check the added content on a display or the like at any time, and thus it is possible to provide an environment where editing by writing can be performed accurately and accurately.

Further, in the above-mentioned image input method, the image input method may further include a step of detecting whether or not writing is being performed on the print medium, wherein the error correction step is a step in which the correction is continuously performed in the correction detection step. It is also effective to replace a part of the digital information converted in the digital information conversion step with the known information.

As a result, in the present invention, the contents of the retouching can be digitized, and can be directly written on a print medium.
The user can check the retouched contents on the display or the printed matter, and also can edit the printed matter at the same time as the editing of the electronic data, so that the user can easily grasp the relationship between the two.

Further, the present invention is a program for causing a computer to execute an error correction process on digital information obtained by converting a two-dimensional code,
The computer causes the computer to execute a storage process of storing a part of the digital information as known information and a replacement process of replacing a part of the digital information with the known information stored in the storage process.

Thus, according to the present invention, it is possible to accurately obtain correct retouching information. That is, information to be corrected can be replaced with known information.
Highly accurate coordinate input becomes possible.

Further, in the above program, when the replacement processing cannot correct the error of the digital information,
It is also effective that a part of the digital information is replaced with the known information, and the error correction process performs an error correction on the digital information with the part replaced.

Thus, according to the present invention, it is possible to improve the error correction rate using known correct information. That is, when error correction fails, information to be corrected can be replaced with known information and error correction can be performed, so that high-speed and high-precision coordinate input can be performed.

Further, in the above-mentioned program, it is also effective to replace a part of the digital information with the known information when the two-dimensional code is continuously input in the replacement process.

As a result, according to the present invention, it is possible to correctly discriminate retouched information for different documents. That is, the replacement means operates only when the two-dimensional code is continuously read, so that when another document is rewritten, erroneous error correction is not performed by information replacement, and Can be correctly separated.

According to the present invention, there is provided the above-described two-dimensional code reader, which is connected via a predetermined network, and includes position information on paper and identification information for uniquely identifying electronic data printed on paper. A program for causing a computer to input a written content on a print medium on which a two-dimensional code including a two-dimensional code is printed in a predetermined arrangement, wherein position information acquired by the two-dimensional code reader is used as the identification information. The computer is caused to execute a location information storage process for storing the information in association with the location information.

Thus, according to the present invention, it is possible to provide an environment in which the electronic document can be freely edited and edited by associating the position information, which is the drawing content, with the information unique to the document.

Further, in the above-mentioned program,
An electronic data identification process for identifying the electronic data based on the identification information acquired by the two-dimensional code reader; and when the identification information is acquired by the two-dimensional code reader, the electronic data identification unit identifies the electronic data. The computer may further execute a display process of displaying the electronic data, and a writing content display process of drawing the writing content based on the position information so as to be superimposed on the electronic data displayed in the display process. It is valid.

Thus, according to the present invention, it is possible to check the added content on the display or the like at any time, so that it is possible to provide an environment where editing by writing can be performed accurately and accurately.

Further, the present invention is the one in which the above-mentioned program is recorded on a recording medium.

Thus, according to the present invention, the above-mentioned program can be recorded on a recording medium and provided.

[0053]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will now be described in detail with reference to the drawings.

FIG. 1 is a plan view of a print document 1 used in the present invention. In the printed document 1, code symbols (codes) 2a to 2d, which are optically readable two-dimensional codes composed of a plurality of black dots (hereinafter, the code of an arbitrary code symbol is set to 2) ) Are arranged in a matrix with black dots arranged regularly in the vertical and horizontal directions as boundaries. The code symbol 2 is printed on a print medium together with the document itself when the document is printed.

The code symbol 2 includes identification (ID) information of an electronic document serving as an original of the document printed together,
And information indicating coordinates on the printing surface. In the example shown in FIG. 1, “horizontal coordinate = 95, vertical coordinate = 10, document ID = 10” is added to the upper left code symbol 2a.
Is encoded, and “horizontal coordinate =
96, vertical coordinate = 10, document ID = 10 ”, code symbol 2c is encoded with“ horizontal coordinate = 95, vertical coordinate = 11, document ID = 10 ”, and code symbol 2d is encoded with“ horizontal coordinate = 96, Vertical coordinate = 11, document ID = 10 "are encoded.

Here, assuming that the two-dimensional code has a horizontal size of 2 mm and a vertical size of 3 mm, when the upper left corner of the two-dimensional code is defined as the upper left corner of the paper, the code symbol 2a having the horizontal coordinate = 95 is located from the origin. It is at a position of 190 mm in the horizontal direction. Similarly, code symbol 2a with vertical coordinate = 10
Is located 30 mm vertically from the origin.

The document ID is unique information of the original electronic document, for example, an identification ID of a database in which the electronic document is stored.
It is. That is, in the code symbol 2a, the upper left corner (the intersection of the vertical line H1 and the horizontal line V1) is located 190 mm horizontally and 30 mm vertically from the upper left of the page, and the ID of the printed document is 10. Information.

Details of the data arranged in the code symbol 2 will be described with reference to FIG. 2, focusing on the code symbol 2a. The code symbols 2a are H1, H constituting a code frame.
2, 7 × 11 cells surrounded by V1 and V2. Note that in this embodiment, a cell is the smallest unit in which dots can be printed. Therefore, in the above case, the code symbol 2a includes a maximum of 77 cells.

The code symbol 2a has a horizontal coordinate area 401 composed of 4 × 2 cells in which data representing horizontal coordinates are arranged, and a 4 × 2 area in which data representing vertical coordinates are arranged.
, A vertical coordinate area 402 composed of cells, a document ID area 403 composed of 4 × 6 cells in which data representing a document ID is arranged, and eight cells in which an error correction code is arranged. Error correction code areas 404 to 407
And is configured. Since one cell corresponds to one bit, the horizontal coordinate area 401 and the vertical coordinate area 4
02 each have a 1-byte capacity, and a document ID area 403
Has a 3-byte capacity, and has error correction code areas 404 to 4.
07 has a capacity of 1 byte (4 bytes in total). In FIG. 2, reference numerals 408 and 409 denote patterns (upper / lower identification code areas) for representing the vertical direction of the code. 4
08 is a 3 × 1 black dot, and 409 is a 2 × 1 dot-less pattern, which is used to determine the upper and lower positions of the code. FIG. 3 shows how bit strings are arranged in each area. However, in 401 to 407,
'1' is the MSB (Most Significant B)
It), and '8' indicates LSB (Least Sign).
(fixant Bit).

Next, the operation of printing an electronic document together with the code symbol 2 as described above will be described in detail with reference to FIGS. However, the creation of the code symbol 2 (two-dimensional code) is performed by the information processing apparatus 21 shown in FIG.
This is executed by the printer driver in the information processing device 23 when the print instruction of the document 31 is executed by the information processing device 23 or the portable information terminal 22.

Referring to FIG. 4, in this operation, the printer driver in the information processing device 23 first
0, the document management database (hereinafter referred to as D
Document 3 to be printed by inquiring of 32)
The document ID of each page is acquired (step S10).
0). Next, the printer driver acquires coordinate information on the document (step S101). When the document ID of the document to be printed and the coordinate information on the document are thus obtained, the printer driver creates data to be encoded into each code symbol 2 by combining them (step S102). This is, for example, document ID = (12345)
6), coordinate information = (24, 123) (however, in mm)
It is created by the method. FIG. 5A shows a schematic configuration of data created at this time.

Next, the printer driver executes step S1.
02 (step S1)
03). In this encoding, for example, the printer driver converts the 6-digit number of the document ID into a 3-byte binary value, and sets the horizontal coordinate to 24/2 = 12, the vertical coordinate to 123/3 = 41, and the horizontal / vertical coordinates. Conversion is performed so that each can be stored in one byte. Thus, the document ID and the coordinate information become data of a total of 5 bytes. FIG. 5B shows a schematic configuration of data created at this time.

When the data is encoded as described above, the printer driver creates an error correction code based on the encoded data (step S104). FIG. 5 (b) →
In the example of (c), a 4-byte error correction code is added to 5-byte data. This error correction code includes
Adopts Reed-Solomon code. The Reed-Solomon code is a powerful error correction method capable of correcting an error in a byte unit, and is capable of correcting an error of less than half of the error correction code length. (See Kodo, "Coding Theory (Basic Computer Science Course 18)", Miyagawa, Iwadare, Imai, etc.). Therefore, in the case of the present embodiment, since the error correction code length is 4 bytes, error correction of 2 bytes is possible.

When the data and the error correction code thus encoded are created, the printer driver assigns them to each cell of the two-dimensional code and creates an image of a matrix in which the two-dimensional code is arranged over the entire page ( Step S105).

After that, the printer driver
2 and the document with the code symbol 2 is hard-outputted using the printer unit of the copying machine 41 (step S10).
6). When printing is completed normally, the document management DB 32
Then, the document ID, page number, and document name of the document normally printed are registered in the document management DB 32 in FIG. 8 (step S107). The details of the document management DB 32 will be described later with reference to the drawings. Further, these operations are repeatedly executed until all pages (or designated pages) in the same document are completed (steps S108 to S109).

FIG. 6 shows an operation procedure for executing the above series of operations. However, the system configuration shown in FIG. 8 is also used to realize this operation.

In this operation procedure, the user first edits the document 31 stored in the storage device 30 (step S200), and issues a print command (step S201).
Thereby, the document 3 is stored in the printer 42 or the copying machine 41.
One hard output is performed. The operation of the printer driver shown in FIG. 4 is executed in step S201 in FIG.

A two-dimensional code (code symbol 2)
FIG. 7 shows a specific example of a document (printed document 1 ′) printed with a mark.
Shown in The print document 1 'is a form document having a predetermined format, and a code symbol 2 is printed in a matrix on the background. FIG. 7 is an enlarged view of a part of the print document 1 ′. Thus, the code symbols 2 are regularly arranged on the print document 1 '.

Next, a configuration for acquiring, as electronic data, information written on the print document 1 created by the above-described operations and operation procedures will be described below.

FIG. 8 is a block diagram showing the configuration of the image input system according to the present embodiment, which allows the user to write on the print document 1 and obtain the written content as electronic data. The lower right part of FIG. 8 shows a schematic configuration of the pen-type coordinate input device 10 according to the present embodiment.

As shown in FIG. 8, the pen-type coordinate input device 10 according to the present embodiment includes a writing tool-like device main body 100 that a person can hold and carry out a writing operation. A writing implement 103,
That is, a tip of a ball-point pen or a mechanical pencil or the like is attached, and it is possible to rewrite a document (printed document 1). The image reading apparatus 110 provided on the side of the apparatus main body 100 is a CCD (Charge Coupled D).
device) and an optical system 111 including a lens and the like, and is a device for reading an image on the printed document 1. The image reading device 110
May be provided with lighting as needed.

The apparatus main body 100 has a microcomputer 101 mounted thereon.
10 are connected. Therefore, the image reading device 11
The image on the print document 1 read at 0 is input to the microcomputer 101.

The microcomputer 101 executes various processes based on the input image. That is, the microcomputer 101
Decodes the input two-dimensional code and detects the coordinates of the two-dimensional code on the paper (details will be described later). In addition, the pen-shaped coordinate input device 10 is configured to output data stored in the microcomputer 101 to the information processing device 21 by wire or wirelessly. In FIG. 8, the image reading device 11
0, a power supply for supplying power to the microcomputer 101, an interface between the microcomputer 101 and the information processing apparatus 21, and the like are not shown.

As shown in FIG. 9, the configuration of the microcomputer 101 is such that a CPU (Centra
l Processing Unit) 1030, RO
M (Read Only Memory) 1040, R
AM (Ramdom Access Memory) 1
020 and a two-dimensional code reader 1010 are connected. These and various external devices are connected via a bus 1000.

A program for controlling the operation of the pen-type coordinate input device 10 and a program for operating the microcomputer 101 are stored in the ROM 1040 in advance. RAM10
Reference numeral 20 temporarily stores an image input from the image reading device 110, intermediate data generated during code reading, and a document ID and coordinate information obtained when a two-dimensional code is decoded. Here, the configuration of the two-dimensional code reader 1010 in FIG. 9 is shown in FIG. 10 and will be described later. The two-dimensional code reader 1010 has a RAM 1
A process is performed to detect a two-dimensional code from the image stored in 020 and decode it to obtain a document ID and coordinate information.

The microcomputer 101 shown in FIG.
LCD (Liquid Crystal Device)
e) Display device 105, LED (Light Emit)
ingDiode) 106 or a buzzer 107 is connected, and information received from the information processing device 21 is displayed on the LED display device 105, or when specific information is received, the LED 106 is blinked or the buzzer 107 is sounded. Notify outside.

A pressure sensor 1 for detecting whether or not the tip portion 102 is in contact with the writing surface is provided on the apparatus main body 100.
04 is provided. That is, the pressure applied to the distal end portion 102 when the distal end portion 102 contacts the writing surface is transmitted to the pressure sensor 104 via the writing implement 103. The pressure sensor 104 senses this pressure and transmits the sensed information to the microcomputer 101.

If the position of the leading end 102 on the printed document 1 is continuously detected using such a pen-shaped coordinate input device 10, the movement locus of the leading end on the printed document 1 can be obtained. . Further, as described above, the writing locus when writing is performed on the paper can be faithfully obtained by the pressure sensor 104 that detects whether the tip end portion 102 is in contact with the writing surface.

However, at this time, if there is no two-dimensional code, it is impossible to read the code even during writing. Therefore, the pen-shaped coordinate input device 10
The user is notified that reading is not possible using the LCD display device 105 or the LED 106.

Here, the configuration and operation of the two-dimensional code reader 1010 shown in FIG. 9 will be described in detail with reference to FIG.

FIG. 10 shows a two-dimensional code reader 1010.
FIG. 3 is a block diagram showing the configuration of FIG. The two-dimensional code reader 1010 is built in the microcomputer 101 inside the pen-shaped coordinate input device 10 shown in FIG. 8 (see FIG. 9).
To this two-dimensional code reader 1010, an image on a paper surface (for example, an 8-bit image) read by the image reader 110 is input.

When an image is input as described above, the two-dimensional code reader 1010 firstly operates the code position detector 101.
In step 1, a frame of one two-dimensional code is detected from a plurality of two-dimensional codes in the image. If the position of the two-dimensional code can be detected, it is input to a data acquisition unit 1012, and data of '0' or '1' is acquired according to each monochrome cell of the two-dimensional code, and Rearrange the data according to the data arrangement rules.

Thereafter, the two-dimensional code reader 1010
Performs error correction on the acquired data in the first error corrector 1014. At the same time, a known document ID is read from the known information memory 1016, and a portion corresponding to the document ID of the data obtained from the two-dimensional code is replaced with a known document ID in the data replacement unit 1013. The second error corrector 1015 also performs a process of performing error correction.

Each error corrector (1014, 101
From 5), the determination information as to whether or not the error correction was successful and the data after the error correction are output. One of the output error-corrected data is selected by a selector 1017 and input to a data decoder 1018. This selector 1017
Is controlled by the output of the pressure sensor 104 in FIG. That is, data to be output is selected according to the presence or absence of retouching detected by the pressure sensor 104.

When the signal output from pressure sensor 104 rises (from no pressure to pressure), selector 1017 selects and outputs the data input from first error corrector 1014. At this time, if the error correction by the first error corrector 1014 fails, it means that the error could not be corrected, which means that the code reading failed. Further, in this case, the data decoder 1018 does not operate, and invalidates the data output. On the other hand, when the pressure sensor 104 is constantly at a pressure, the selector 10
Reference numeral 17 selects and outputs the data input from the second error corrector 1015. At this time, if error correction by the second error corrector 1015 fails, it means that code reading has failed. In addition, in the case of no pressure, the state is not in the state of being retouched, and the selector 1017 does not select any input.

The data corrected in this way is the document I
D and coordinate information, and the document I in the error-corrected data
Only the D part can be extracted. The extracted document ID is
The information is stored in the known information memory 1016 as known information.

A specific example of data replacement will be described with reference to the table shown in FIG. In the table of FIG. 11, the first line is correct data, that is, data generated by encoding to generate an error correction code. The second line is the image reading device 11.
This is data obtained by extracting a two-dimensional code from the image read at 0 and reconstructing it from dots of the code. In this specific example,
In the reconstructed data, there are errors in the first and second document IDs and the first error correction information. Therefore, since three errors are included in the data, error correction becomes impossible in this embodiment. However, by replacing the document ID as known information, the error in the document ID portion is eliminated, and only the first error correction information becomes an error.
Is obtained.

The data selected and output by the selector 1017 is input to the data decoder 1018, and is decoded into coordinate information on the page and the document ID. The ID on the paper is shown in FIG.
, Horizontal coordinate = 24 mm, vertical coordinate = 123 mm,
Document ID = 23. Using the coordinate information and the coordinate information on the image of the two-dimensional code that has been successfully decoded, the pen tip coordinate calculator 1019 calculates the coordinates of the pen tip on the paper surface (details will be described later). Thus, the position of the tip 102 of the pen-type coordinate input device 10 is determined.

When the pressure sensor 104 rises,
The selector 1017 may execute the following selection. That is, when the pressure sensor 104 rises (from no pressure to pressure), the selector 1017 sets the first error corrector 10
14 is selected, at this time, the first error corrector 10
If the error correction has failed at 14, the selector 1017 selects the output of the second error corrector 1015. If the second error corrector 1015 also fails to correct the error, it means that the error could not be corrected, which means that the code reading failed. By controlling the selection in this way, if a new revision is made, if the revision is to the same document, the error correction rate of the second error corrector 1015 is improved, which is more advantageous than the above-described method.

Next, the code position detector 1 shown in FIG.
011 will be described in detail with reference to FIG. FIG.
Referring to, a code position detector 1011 includes a dot detector 1101 that detects a dot from an input image from the image reading device 110, a code frame detector 1102 that detects a dot forming a code frame from the detected dot, and Consists of

The operation of the dot detector 1101 will be described with reference to FIG. Considering the pixel Z in FIG. 13, the dot detector 1101 determines that there is no already detected dot in the hatched pixels (A to H) around the pixel of interest Z, and When the pixel value of Z is equal to the surrounding pixels (I to
When the pixel value is smaller than any pixel value of X) by a predetermined value (Th) or more, the target pixel Z is detected as a code dot (for example, black = 0 and white = 255 in the input image). In addition, the smaller the predetermined value (Th) is, the easier it is to detect a dot. However, at the same time, noise is also detected as a dot, and there is a possibility that an error occurs in the detected data. If Th is large, errors can be reliably reduced without detecting noise, but it is difficult to detect a code frame, and the coordinate acquisition rate decreases. Therefore, an appropriate value is set for Th in consideration of this.
FIG. 14 shows a coordinate acquisition rate according to the size of Th. The table shown in FIG. 14 shows both data when the document ID is replaced and when it is not replaced.

The code frame detector 11 shown in FIG.
02 will be described in detail with reference to FIG. The code frame detector 1102 tracks dots in an input image in order to detect dots forming a code frame from the detected dots. The tracking route at this time is shown in FIGS.
This will be described with reference to FIG. First corner detector 1 in FIG.
Reference numeral 201 denotes a certain dot (this dot is denoted by “X”) from the dot-detected image input from the dot detector 1101.
) Is a corner of the code. The details of this determination will be described later.

When the dot X at the corner is specified in this manner, the code frame detector 1102 sets the dot tracker 1202
, The dot X is the starting point (this is called the first corner)
The second corner candidate pixel (A, B, C, D) is detected by tracing eight pixels of the code frame composed of dots from the first corner in four directions. The code frame detector 1102 determines whether the second corner candidate pixel detected by the dot tracker 1202 is the second corner (B, D).
The determination is made in the corner detector 1203.

When the second corner is specified in this way, the court frame detector 1102 uses the dot tracker 1204 to determine the 12th code frame composed of dots from the second corner.
The third corner candidate pixel (G, E) is detected by tracing the pixels in a direction rotated clockwise by 90 degrees from the dot tracing direction in the dot tracing device 1202. Similarly, the code frame detector 1102 includes the dot tracker 120
4 is the third corner candidate pixel detected at the third corner (G,
The third corner detector 1205 determines whether or not E).

When the third corner is specified in this manner, the code frame detector 1102 uses the dot tracker 1206 to divide the eight pixels of the code frame composed of dots from the third corner by the dot tracker 1206. 9 from the dot tracking direction
By tracking in the direction rotated 0 degrees clockwise,
A fourth corner candidate pixel (C, A) is detected. Similarly, the code frame detector 1102 includes a dot tracker 1206
Is the fourth corner candidate pixel detected at the fourth corner (C, A)
Is determined by the fourth corner detector 1207 which detects whether or not.

Further, the code frame detector 1102 detects the dots constituting the code frame between the first corner and the fourth corner specified above by using the dot tracker 1208. By using the code frame detector 1102 configured as described above, it is possible to detect the code frames of up to two two-dimensional codes and detect the coordinates of the dots constituting the code frames on the image.

The first corner detector 12 described above
01 will be described with reference to FIG. As shown in FIG. 17A, the first corner detector 1201 detects a surrounding dot detector 1211 that detects whether four or more dots exist around a target pixel where a dot exists, and And a point symmetric pair detector 1212 for detecting two dot pairs whose target pixel is point symmetric from the surrounding dots.

The surrounding dot detector 1211 outputs the target pixel N
Is detected around the target pixel N in 17 × 17 pixels centered at. In the case of FIG.
There are six pixels of F. Therefore, the surrounding dot detector 1211 detects these as surrounding dot pixels.
Further, the point target pair detector 1212 includes, among the surrounding dot pixels A to F detected by the surrounding dot detector 1211,
Two pairs whose intermediate points are close to N are detected. FIG.
In the case of (b), two sets of (B, D) and (C, F) are detected. The remaining A and E are determined to be noise and are removed. In this way, the dot N of the pixel of interest and the surrounding 2
When a pair of point symmetric pairs is detected, the first corner detector 12
01 detects the target pixel N as the first corner.

Next, the details of the dot tracker 1202 are shown in FIG.
8 will be described. FIG. 18 shows dots constituting the vicinity of the corner of the code. X is a corner dot (first corner), and the other AI are dots constituting a code frame. In this description, from X to D, E,
The case where dots are tracked in the direction of F will be described.
For simplicity of explanation, A to I and X are each regarded as a coordinate vector.

In this tracking, the dot tracker 1202
Calculates the following (Equation 1). Note that Y is an estimated vector of the dot E. A to D are first corner detectors 1
It is already known because it has already been detected at 201. Y = 2D + X (Equation 1) Next, the dot tracker 1202 searches for a dot E in 5 × 5 pixels around Y. As a result of this search, dot E
Exists, the dot tracker 1202 calculates the following (Equation 2). In this (Equation 2), Y is an estimated vector of the dot F. Y = 2ED (Equation 2) Thereafter, the dot tracker 1202 repeats the above tracking seven times to detect a second corner candidate pixel. However, for example, in the example shown in FIG. 16, four tracking directions (FIG. 16:
X → A, X → B, X → C, X → D). The dot detector 1202 transfers the information of all the detected second corner candidate pixels to the second corner detector 1203.

The basic operation of the second corner detector 1203 is the same as that of the first corner detector 1201. Another difference is that there are two dots to start tracking,
Tracking is performed in one direction for each dot (Fig. 1
6: B → G, D → E) and a point where the dot tracking operation is repeated 11 times for each tracking. By operating in this manner, the second corner detector 1203 detects a third corner candidate pixel (G, E in FIG. 16).

As described above, the third corner detector 1205 detects whether or not the third corner candidate pixel (G, E in FIG. 16) which can be tracked by the dot tracker 1204 is at the third corner. The basic operation is the same as that of the above-described first and second corner detectors (1201, 1203). In this description, it is assumed that the dots G and E in FIG. 16 are detected as the third corners by the third corner detector 1205.

The dot tracker 1206 tracks dots in two directions (FIG. 16: G → C, E → A). The number of times of tracking is seven times, which is the same as that of the dot tracker 1202. With this operation, the dot tracker 1206 detects the dots C and A in FIG. 16 as the fourth corner candidate pixels.

The dot tracker 1208 is the dot tracker 1
The configuration is the same as that of C → X, A → in FIG.
It traces 11 times in the direction of X and reaches the dot X. Since X is already known to be the first corner, the code frame is detected by the tracking and the tracking.

By operating as described above, the code frame of code symbol 2 can be detected. It should be noted that which code to use when decoding the two-dimensional code is preferably given priority to the one with the larger horizontal coordinate of the code center on the image. However,
If one of the codes cannot be decoded, the decoding is performed using the other code.

Next, the data acquisition unit 101 in FIG.
Operation 2 will be described in detail with reference to FIG. However, FIG.
In the description of No. 9, the dots constituting the code frame are defined as a1 to a7, b1 to b11, c1 to c7, except for the four corners.
d1 to d11. When acquiring the data of the code, the data acquiring unit 1012 detects the intersection of the horizontal line and the vertical line connecting them (step S40 in FIG. 19B).
0). That is, the coordinates of the intersection of the straight line connecting a1 and c1 and the straight line connecting b2 and d2 are detected. Next, the presence or absence of a dot included in a 3 × 3 pixel area centered on the coordinates of the intersection is detected (step S40 in FIG. 19B).
1). In the case of FIG. 19, there is no dot, and the acquired data is “0”. The data acquiring unit 1012 acquires code data by performing this operation on all data included in one code symbol 2. Further, the data acquiring unit 1012 acquires final code data by reconstructing the acquired data according to the data array shown in FIG.

Next, the configuration of the pen tip coordinate calculator 1019 in FIG. 10 will be described in detail with reference to FIG. Referring to FIG. 25, the pen tip coordinate calculator 1019
Is composed of a projection parameter calculator 1901 and a pen tip coordinate converter 1902. In this configuration, the projection parameter calculator 1901 stores the coordinates of the code corner on the image (hereinafter, corner image coordinates) and the corresponding coordinates of the code corner on the paper (hereinafter, corner paper surface coordinates) as data. Input from the decoder 1018. Therefore, the projection parameter calculator 1901 calculates the projection parameters from the input corner image coordinates and the corner paper surface coordinates.

Here, the calculation of the projection parameters will be described in detail with reference to FIG. FIG. 21A shows the coordinates of the corners (As to Ds) of the code in the image and the coordinates of the tip end portion 102 (Ps) of the pen-type coordinate input device 10. However, in this embodiment, the coordinates of Ps are always constant. This is because the pen-type coordinate input device 10 uses the image reading device 1
This is because 10 and the tip 102 are fixed. Therefore, depending on the configuration of the pen-shaped coordinate input device 10, the distal end portion 102 may be inside the image captured by the image reading device 110 or may be outside the image. If the coordinates are outside the image, the coordinates will be negative values or exceed the maximum value of the coordinates of the image.

FIG. 21B shows the coordinates of the corners (Ar to Dr) of the code and the coordinates of the tip 102 (Pr) of the pen-type coordinate input device 10 on the paper. Here, As to Ds are coordinates calculated by the code frame detection in the above-described operation, and Ps is fixedly obtained because the positional relationship between the image reading device 110 and the distal end portion 102 is fixed as described above. Things. Since Ar is determined by decoding the code, the adjacent corners Br to Dr are automatically determined. Eight one-dimensional equations (eight-ary linear equations) obtained by substituting the coordinates obtained in this way into a projection return equation shown in (Equation 3) below
Are solved, the parameters b1 to b8 of the conversion coefficient in (Equation 3) are specified.

[0110]

(Equation 1) Therefore, the coordinates (Pr) of the leading end portion 102 on the paper surface are:
The parameters b1 to b8 can be calculated by substituting the coordinates (Ps) of the front end portion 102 in the image into the specified (Equation 3) and converting the image coordinates to the paper surface coordinates.

The two-dimensional code reader 101 described above
In 0, the code is read by hardware, but this may be performed by software. In such a configuration, a program for realizing the two-dimensional code reading method is stored in the ROM 1040 of the microcomputer 101, and the instructions of the program are sequentially loaded into the CPU 1030 to execute the instructions, thereby reading the two-dimensional code. Processing is performed. The processing procedure in such a configuration will be described in detail with reference to the flowchart of FIG.

Referring to FIG. 22, in the two-dimensional code reading process, first, the position of the two-dimensional code is extracted with respect to the input image (step S10). After that, data of '0' or '1' is obtained according to the black and white (presence or absence of a dot) of the two-dimensional code, and the obtained data is rearranged (step S11).

Next, it is determined whether or not the acquired data is continuously acquired (or whether or not the leading end portion 102 is constantly pressed against the paper) (step S12). If it is obtained continuously (Yes in step S12), the document I in the obtained data
The part D is replaced with known information (the document ID acquired and held before) (step S13), and the process proceeds to step S14. On the other hand, if the acquired data is not one that has been continuously acquired (No in step S12), step S13 is omitted and the process proceeds to step S14.

In step S14, error correction is performed on the acquired data (with / without data replacement) (step S14). If the error correction is successful in step S14 (Yes in step S15), the decoded known information (document ID) is stored (step S1).
6) Then, the original data (coordinate information) is restored (step S17). After restoring the coordinate information in this way, the coordinates on the paper surface of the tip 102 of the pen-type coordinate input device 10 are obtained using the above-described method (step S18). On the other hand, if the error correction in step S14 is unsuccessful (step S15), the process ends.

The processing of code position detection, data acquisition, coordinate / document ID restoration, and pen tip coordinate calculation are performed by the code position detector 1011, data acquirer 1012, data decoder 1018, pen tip coordinates shown in FIG. It corresponds to each block of the calculator 1019, and the procedure is as described above.

Another example of the two-dimensional code reading method will be described with reference to a flowchart shown in FIG. FIG.
The difference from the method described in (1) is that error correction is performed only when data is not continuously obtained, and when the error cannot be corrected, the document ID portion is replaced and error correction is performed. When rewriting the same document, using the method of FIG. 23 improves error correction.

Next, an image input system for acquiring additional information by reading a two-dimensional code as described above will be described in detail with reference to the system configuration diagram of FIG. 8 and the flowchart of FIG. It is assumed that a two-dimensional code is added to the print document 1 and that the pen-type coordinate input device 10 rewrites the print document 1.

Referring to FIG. 24, in the present operation, by adding to the print document 1 using the pen-type coordinate input device 10,
The two-dimensional code on the print document 1 is read, and a document ID and coordinate information are obtained (step S300). Also,
In step S300, the acquired document ID and coordinate information are transferred to the information processing device 21 in real time, and further transferred from the information processing device 21 to the information processing device 23 that manages the document management database 32.

Based on the received document ID, the information processing apparatus 23 specifies a document (page of: hereinafter referred to as document information) which is currently added from the document management database 32 (step S301). Step S301
In, the specified document information is transmitted to the information processing device 21, and further transferred from the information processing device 21 to the pen-type coordinate input device 10. The document specified in this description is the identification number (ID) (= 123456) in FIG.
Page 1 of “patent.doc”.

When the document information is specified in this manner, the pen-type coordinate input device 10 displays the specified document information to the user using the LCD display device 105 or the like, and the information processing device 21 specifies the document information. File entity (in this description,
For example, “patent.doc” in FIG. 25 is opened by an application (word processor software or the like) associated with the “patent.doc”, displayed on a display (not shown) connected to the information processing apparatus 21 to enter an editing state ( Step S302).

Therefore, the information processing device 21 creates a new graphic object by drawing the coordinate information sequentially transmitted from the pen-type coordinate input device 10 on the document “patent.doc” in the edited state ( Step S3
03 to S307). In the drawing process, a new drawing object is opened in the document window (step S30).
3) It can be realized by acquiring coordinate information from the received data (step S304) and connecting these with a line to draw (step S304). Also, the coordinate information acquired in step S304 is stored in a file as a predetermined sequence text while maintaining the order (step S306). Steps S304 to S3
The processes up to 06 are repeatedly executed until the end of the retouching by the user (No in step S307).

When the rewriting by the user is completed (Yes in step S307), the pen-type coordinate input device 10 transmits a signal indicating the end of the rewriting to the information processing device 23, and the information processing device 23 having received the signal indicating the end of the rewriting is Then, the drawing on the window ends (step S308). By operating in this manner, “patent.d” is stored in the document management DB 32.
One object corresponding to "oc" is added. FIG. 25 shows a data configuration of the document management DB 32 according to the present embodiment.

With the configuration and operation described above, in this embodiment, the edited information is displayed on the display of the computer in real time, and it can be immediately confirmed whether or not the edited information is correctly processed. This is a great advantage for the user. In addition, the information processing device 23 simultaneously stores the received coordinate information as a number sequence text as a separate file, so that when the user wants to open the application later and check the edited data, for example, when the document is huge, the user can quickly check the edited data. When it is not possible, only the added data can be displayed and confirmed, which is effective.

[Other Embodiments] Each of the above-described embodiments is merely an example of a preferred embodiment of the present invention, and the present invention may be variously modified and implemented without departing from the gist of the present invention. Is possible.

[0125]

As described above, according to the first aspect of the present invention, it is possible to obtain correct retouched information with high accuracy. That is, information to be corrected can be replaced with known information, so that highly accurate coordinate input can be performed.

Further, according to the second aspect of the present invention, it is possible to improve the error correction rate using known correct information. That is, when error correction fails, information to be corrected can be replaced with known information and error correction can be performed, so that high-speed and high-precision coordinate input can be performed.

Further, according to the third aspect of the present invention, it is possible to correctly separate added information for different documents. That is, the replacement means operates only when the two-dimensional code is continuously read, so that when another document is rewritten, erroneous error correction is not performed by information replacement, and Can be correctly separated.

Further, according to the fourth aspect of the present invention, it is possible to correctly associate the rewritten document with the original electronic document. In other words, by making known information into document-specific information, it becomes possible to associate the reprinted print document with the original electronic document.

Further, according to the fifth aspect of the invention, by managing the position information as the drawing content and the information unique to the document in association with each other, it is possible to provide an environment in which the electronic document can be freely edited by rewriting. Becomes possible.

Further, according to the invention described in claim 6, it is possible to check the added content on a display or the like at any time, so that it is possible to provide an environment where editing by writing can be performed accurately and accurately. Become.

Further, according to the invention of claim 7, since the contents of the retouching can be digitized and directly written on the print medium, the user can check the retouched contents on the display or the like, and on the printed matter. Further, since it is possible to edit the printed matter simultaneously with the editing of the electronic data, the user can easily grasp the relationship between the two.

According to the invention described in claim 8, it is possible to obtain correct retouching information with high accuracy. That is, information to be corrected can be replaced with known information, so that highly accurate coordinate input can be performed.

Further, according to the ninth aspect of the present invention, it is possible to improve the error correction rate using known correct information. That is, when error correction fails, information to be corrected can be replaced with known information and error correction can be performed, so that high-speed and high-precision coordinate input can be performed.

Further, according to the tenth aspect of the present invention, it is possible to correctly classify added information for different documents. That is, the replacement means operates only when the two-dimensional code is continuously read, so that when another document is rewritten, erroneous error correction is not performed by information replacement, and Can be correctly separated.

Further, according to the eleventh aspect of the present invention, it is possible to correctly associate a rewritten document with an original electronic document. In other words, by making known information into document-specific information, it becomes possible to associate the reprinted print document with the original electronic document.

According to the twelfth aspect of the present invention, an environment in which editing by electronically editing an electronic document can be freely provided by associating and managing position information as drawing content and information unique to the document. Becomes possible.

Further, according to the thirteenth aspect of the present invention, it is possible to check the added content on a display or the like at any time, so that it is possible to provide an environment in which editing by writing can be performed accurately and accurately. Become.

Further, according to the fourteenth aspect of the present invention, since the contents of the retouching can be digitized and directly written on the print medium, the user can check the retouched contents on a display or the like or on a printed matter. Further, since it is possible to edit the printed matter simultaneously with the editing of the electronic data, the user can easily grasp the relationship between the two.

According to the fifteenth aspect of the present invention, it is possible to accurately obtain correct retouching information. That is, information to be corrected can be replaced with known information, so that highly accurate coordinate input can be performed.

Further, according to the invention of claim 16, it is possible to improve the error correction rate using known correct information. That is, if error correction fails,
Since error correction can be performed by replacing information to be corrected with known information, it is possible to input coordinates at high speed and with high accuracy.

Further, according to the seventeenth aspect of the present invention, it is possible to correctly classify added information for different documents. That is, the replacement means operates only when the two-dimensional code is continuously read, so that when another document is rewritten, erroneous error correction is not performed by information replacement, and Can be correctly separated.

According to the eighteenth aspect of the present invention, it is possible to provide an environment where the electronic document can be freely edited and edited by associating and managing the position information as the drawing content and the information unique to the document. Becomes possible.

Further, according to the nineteenth aspect of the present invention, it is possible to check the added content on a display or the like at any time, so that it is possible to provide an environment in which editing by writing can be performed accurately and accurately. Become.

According to the twentieth aspect of the present invention, the program can be provided by being recorded on a recording medium.

[Brief description of the drawings]

FIG. 1 is a diagram for explaining a two-dimensional code (code symbol 2) arranged on a print document 1 according to an embodiment of the present invention.

FIG. 2 is a diagram showing details of data arranged in a code symbol 2;

FIG. 3 is a diagram showing an arrangement of bit strings in each area shown in FIG. 2;

FIG. 4 is a flowchart illustrating an operation of a printer driver incorporated in the information processing apparatus 23 according to an embodiment of the present invention.

FIG. 5 is a diagram for explaining data created in the operation of FIG. 4 step by step;

FIG. 6 is a flowchart illustrating a user's operation procedure when outputting a print document 1 to which a two-dimensional code (code symbol 2) is attached in one embodiment of the present invention.

FIG. 7 is a diagram showing a specific example of a print document hard-output in an embodiment of the present invention.

FIG. 8 is a block diagram showing a configuration of an image input system according to one embodiment of the present invention.

9 is a block diagram showing a configuration of a microcomputer 101 in FIG.

FIG. 10 shows a two-dimensional code reader 1010 in FIG.
FIG. 3 is a block diagram showing the configuration of FIG.

FIG. 11 is a table illustrating a specific example of data replacement according to an embodiment of the present invention.

FIG. 12 is a block diagram showing a configuration of a code position detector 1011 in FIG.

FIG. 13 is a diagram for explaining the operation of the dot detector 1101 in FIG.

FIG. 14 is a table showing a coordinate acquisition rate according to the magnitude of Th in one embodiment of the present invention.

FIG. 15 is a block diagram showing a configuration of a code frame detector 1102 in FIG.

FIG. 16 is a diagram for explaining a tracking path of the code frame detector 1102 in FIG.

17A is a block diagram showing a configuration of a first corner detector 1201, and FIG. 17B is a block diagram showing a configuration of the first corner detector 12.
It is a figure for explaining operation of No. 01.

FIG. 18 is a diagram for explaining the operation of the dot tracker 1202.

FIG. 19 is a diagram for explaining the operation of the data acquisition unit 1012 in FIG.

20 is a block diagram showing a configuration of a pen tip coordinate calculator 1019 in FIG.

FIG. 21 is a diagram for explaining calculation of a projection parameter in one embodiment of the present invention.

FIG. 22 is a flowchart illustrating a two-dimensional code reading process according to an embodiment of the present invention.

FIG. 23 is a flowchart showing another example of the two-dimensional code reading process in one embodiment of the present invention.

FIG. 24 is a flowchart showing the operation of the image input system according to one embodiment of the present invention.

FIG. 25 is a table showing a data configuration of a document management database 32 according to an embodiment of the present invention.

[Explanation of symbols]

1, 1 'printed document 10. Pen-type coordinate input device 21, 23 Information processing device 22 Mobile information terminals 30 storage devices 31 documents 32 Document Management Database 41 Copier 42 Printer 43 Scanner 50 LAN 100 main unit 101 microcomputer 102 Tip 103 writing implement 104 pressure sensor 105 LCD display device 106 LED 107 Buzzer 110 Image reading device 111 optical system 112 photoelectric conversion element 401 horizontal coordinate area 402 vertical coordinate area 403 Document ID area 404-407 Error correction code area 408, 409 Upper and lower identification code area 1000 bus 1010 2D code reader 1020 RAM 1030 CPU 1040 ROM 1011 Code position detector 1012 Data acquisition device 1013 Data Replacer 1014 First error corrector 1015 Second error corrector 1016 Known information memory 1017 selector 1018 Data decoder 1019 Pen tip coordinate calculator 1101 dot detector 1102 Code frame detector 1201 First corner detector 1202 dot tracker 1203 2nd corner detector 1204 dot tracker 1205 Third corner detector 1206 dot tracker 1207 4th corner detector 1208 dot tracker 1211 Surrounding dot detector 1212 Point symmetric pair detector 1901 Projection parameter calculator 1902 Pen tip coordinate converter

   ────────────────────────────────────────────────── ─── Continuation of front page    (72) Inventor Makoto Yamazaki             1-3-6 Nakamagome, Ota-ku, Tokyo Stock             Inside the company Ricoh (72) Inventor Tomohiko Beppu             1-3-6 Nakamagome, Ota-ku, Tokyo Stock             Inside the company Ricoh (72) Inventor Toshiyuki Furuta             1-3-6 Nakamagome, Ota-ku, Tokyo Stock             Inside the company Ricoh (72) Inventor Nobuyuki Doi             1-3-6 Nakamagome, Ota-ku, Tokyo Stock             Inside the company Ricoh (72) Inventor Hitoshi Hattori             1-3-6 Nakamagome, Ota-ku, Tokyo Stock             Inside the company Ricoh F term (reference) 5B047 AA27 BA03 CB22                 5B072 AA01 AA02 CC21 DD21 HH07                       JJ12 LL11 LL18 MM02

Claims (20)

[Claims] An image input unit that inputs one or more two-dimensional codes printed on a print medium as an image; a digital information conversion unit that converts the input two-dimensional code into digital information; A two-dimensional code reading device, comprising: an error correction unit that performs error correction on information; and a decoding unit that decodes the digital information on which the error correction has been performed, wherein the error correction unit includes a part of the digital information. Storage means for storing the digital information as known information, and replacement means for replacing a part of the digital information converted by the digital information conversion means with the known information stored in the storage means. Dimension code reader. 2. The error correction unit, when error correction of the digital information converted by the digital information conversion unit is not possible, the replacement unit replaces a part of the digital information with the known information. 2. The two-dimensional code reader according to claim 1, wherein an error correction is performed on the partially substituted digital information. 3. When the two-dimensional code is continuously input as an image from the image input unit, the replacement unit converts a part of the digital information converted by the digital information conversion unit into the known information. 2. The two-dimensional code reader according to claim 1, wherein the two-dimensional code reader is replaced. 4. The apparatus according to claim 1, wherein the known information is unique to data printed on a print medium.
The two-dimensional code reader according to any one of the above. 5. A method including position information on a sheet of paper and identification information for uniquely identifying electronic data printed on the sheet of paper.
An image input device for inputting a written content on a print medium on which a dimensional code is printed in a predetermined arrangement, wherein the two-dimensional code reader according to any one of claims 1 to 4, An image input device, comprising: position information storage means for storing position information obtained by a code reading device in association with the identification information. 6. An electronic data specifying means for specifying the electronic data based on the identification information obtained by the two-dimensional code reading device, and when the identification information is obtained by the two-dimensional code reading device, Display means for displaying the electronic data specified by the electronic data specifying means, and writing content display means for drawing the writing content based on the position information, superimposed on the electronic data displayed by the display means, 6. The image input device according to claim 5, comprising: 7. The two-dimensional code reader includes a writing unit for writing on the print medium, and a writing detection unit for detecting whether or not writing has been performed by the writing unit. The replacement unit replaces a part of the digital information converted by the digital information conversion unit with the known information when the writing detection unit detects that the writing by the writing unit is continuously performed. 7. The image input device according to claim 5, wherein: 8. An image input step of inputting one or more two-dimensional codes printed on a print medium as an image, and a digital information conversion for converting the two-dimensional code input in the image input step into digital information. A two-dimensional code reading method, comprising: an error correction step of performing error correction on the digital information; and a decoding step of decoding the digital information on which the error correction has been performed, wherein the error correction step comprises: A two-dimensional code reading method, wherein a part of digital information is stored as known information, and the stored known information replaces a part of the digital information converted in the digital information conversion step. 9. The method according to claim 1, wherein the error correcting step replaces a part of the digital information with the known information when the digital information converted in the digital information converting step cannot be corrected. 9. The two-dimensional code reading method according to claim 8, wherein error correction is performed on the obtained digital information. 10. When the two-dimensional code is continuously input as an image in the image input step, the error correction step includes a step of converting a part of the digital information converted in the digital information conversion step into the known information. 9. The two-dimensional code reading method according to claim 8, wherein 11. The two-dimensional code reading method according to claim 8, wherein the known information is unique to data printed on a print medium. 12. A handwritten content on a print medium on which a two-dimensional code including position information on the paper and identification information for uniquely identifying electronic data printed on the paper is printed in a predetermined arrangement is input. 12. A two-dimensional code reading method according to claim 8, wherein the position information obtained by the two-dimensional code reading method is stored in association with the identification information. An image input method, comprising: an information storing step. 13. An electronic data specifying step of specifying the electronic data based on the identification information obtained by the two-dimensional code reading method, and a display step of displaying the electronic data specified in the electronic data specifying step. The image input method according to claim 12, further comprising: a writing content drawing step of drawing writing content based on the position information so as to be superimposed on the electronic data displayed in the display step. 14. A rewriting detecting step for detecting whether or not writing is performed on the print medium, wherein the error correcting step detects that rewriting is continuously performed in the rewriting detecting step. 2. The method according to claim 1, wherein when the conversion is performed, a part of the digital information converted in the digital information conversion step is replaced with the known information.
14. The image input method according to 2 or 13. 15. A program for causing a computer to execute an error correction process on digital information obtained by converting a two-dimensional code, a storage process for storing a part of the digital information as known information, And a replacement process for replacing a part of the digital information with known information stored in a storage process. 16. The replacement process, when error correction of the digital information is impossible, replacing a part of the digital information with the known information, and the error correction process is performed by replacing the digital information with the partially replaced digital information. 16. The program according to claim 15, wherein error correction is performed on the program. 17. The program according to claim 15, wherein the replacement process replaces a part of the digital information with the known information when a two-dimensional code is continuously input. 18. A two-dimensional code reader according to any one of claims 1 to 4, which is connected via a predetermined network to uniquely identify positional information on paper and electronic data printed on paper. A program for causing a computer to input a written content on a print medium on which a two-dimensional code including identification information for printing is printed in a predetermined arrangement, and wherein the position information acquired by the two-dimensional code reader is provided. And a program for causing the computer to execute a position information storing process of storing the information in association with the identification information. 19. An electronic data specifying process for specifying the electronic data based on the identification information obtained by the two-dimensional code reading device, and when the identification information is obtained by the two-dimensional code reading device, A display process for displaying the electronic data specified by the electronic data specifying unit; and a writing content display process for drawing the writing content based on the position information so as to be superimposed on the electronic data displayed in the display process. 19. The program according to claim 18, which is executed by said computer. 20. A recording medium on which the program according to claim 15 is recorded.